On turning 40 today

Holy crap.

In case you’re wondering how I spent such a milestone of a day: well, I spent hours of it at an important virtual grant review meeting with the Department of Defense. Alas, when it came time for my own big presentation at that meeting—about what my students and I had done over the past five years to lay the theoretical foundations for the recent achievement of quantum computational supremacy—I’d uploaded the completely wrong PowerPoint file (it was something.pptx rather than something.ppt, where they weren’t two versions of the same presentation). Sorting this out took about 10 minutes, destroyed my momentum, and wasted everyone’s time. I partly blame the Microsoft Teams platform, whose limitations as conferencing software compared to Zoom necessitated emailing my presentation in the first place. But of course, part of the blame rests with me.

I had to explain apologetically to the US Department of Defense that I’m no good with tech stuff—being a mere computer science PhD. And unlike many of my colleagues (who I envy), back in my youth—for at age 40 I’m no longer young—I never had enough time to become both the kind of person who might earn a big grant to do quantum computing theory, and the kind of person who’d be minimally competent at the logistics of a review meeting for such a grant.

Forty years. Seven-eighths of those years, aware of the finiteness of the speed of light and of its value. Four-fifths of them, aware of the grislier details of the Holocaust. Three-quarters of them, aware of what it means to write code. Two-thirds of them, aware of polynomial versus exponential time. More than half of them trying to understand the capabilities and limitations of quantum computers as my day job. And then, rounding the corner, more than a third of the years writing this blog, a third of them being a professor, a quarter of them married, a fifth of them raising kids, a thirtieth of them in the midst of a global pandemic.

I didn’t even come close to achieving everything I hoped I would in my thirties. At least a half-dozen major papers, ones I expected would’ve been finished years ago (on the mixing of coffee and cream, on complexity and firewalls and AdS/CFT, on certified random numbers from sampling-based quantum supremacy experiments, on the implications of the Raz-Tal oracle separation, …), still need to be revised or even written. Other projects (e.g., the graphic novel about teaching math to Lily) were excitedly announced and then barely even started. I never wrote most of my promised blog post about the continuum hypothesis, or the one about Stephen Wolfram’s recrudescent claims of a unified theory of physics. And covid, which determined the world’s working conditions while we were running out the clock, turned out not to be a hyper-productive time for me. That’s how you know I’m not Newton (well, it’s the not the only way you know).

Anyway, during the runup to it, one’s 40th birthday feels like a temporal singularity, where you have to compress more and more of what you’d hoped to achieve before age 40 as you get closer and closer to it, because what the hell is there on the other side? They‘re over-40 and hence “old”; you’re under-40 and hence still “young.”

OK, but here I am on the other side right now, the “old” side, and I’m still here, still thinking and writing and feeling fairly continuous with my pre-singularity embodiment! And so far, in 16 hours on this side, the most senile thing I’ve done has been to email the wrong file attachment and thereby ruin an important funding presenta… you know what, let’s not even go there.

If you feel compelled to give me a 40th birthday present, then just make it a comment on this post, as short or long as you like, about what anything I said or did meant for you. I’m a total softie for that stuff.

112 Responses to “On turning 40 today”

  1. Raoul Ohio Says:

    Happy Birthday!

    Maybe read a nice book for a self BD gift! Watson’s “Bessel Functions” is always a treat.

  2. Jay L Gischer Says:

    Happy Birthday. Don’t worry, it’s still possible to finish writing those papers. And as you move into your forties, it will become more significant to you to do it.

  3. Dwarkesh Patel Says:

    Happy birthday Professor Aaronson!!!

    I have gained a lot of valuable mathematical / theoretical intuition by taking your classes. Already, what you have taught me has helped me in my other classes and given me a much better understanding of classical algorithms and proofs. I expect it (contra Caplan) to greatly carry over into the engineering and design that I will do in my career.

    Aside from the tangible lessons, simply getting to follow along with your lectures and ask you questions was an irreplaceable experience. Imagine a completely average laborer getting to study with one of the most skilled stonemasons in his generation. He will not understand most of the stonemason’s techniques nor absorb most of his skills, but his appreciation for the craft and ambition for excellence will grow enormously. And he will be grateful for the experience 🙂

  4. Bob Jacobs Says:

    Happy birthday Scott!
    On top of a comment explaining what I appreciate about you, I will also make a donation to a charity of your choice. Anyway, I most appreciate your posts that directly explaining this research field, especially when it gets more into the philosophical stuff like you did with the integrated information theory of consciousness. Speaking of philosophy, do you think you’ll ever take a look at non-classical logics, like paraconsistent logic?

  5. Ryan O'Donnell Says:

    Happy birthday, Scott! I’ve been reading your blog for about three-eighths of your life 🙂 I think maybe only Terry Tao’s can try to compete for long-term appeal…

  6. Daniel Says:

    Happy birthday! I’m one of the (I suspect many) people who read your blog and don’t normally comment, but I consistently really enjoy your writing and this little window into a field that’s normally hidden behind a frosted glass wall of mystique. I’m nearing 30 so can well relate to your analogy of a temporal singularity – but the fact that both milestones feel so similar suggests that they aren’t really as relevant as they feel.

  7. Paul Hoffman Says:

    I give you the present of saying “Gaza” and “quantum supremacy” so you can see which causes more inflamed follow-on comments.

  8. Shaked Koplewitz Says:

    Happy Birthday!

    My (somewhat depressing) reference for turning forty is Asimov’s Forward The Foundation, which remains my favourite Asimov book, and is basically a series of high-speed reflections about the second half of his life. Your talking about achievements feels a lot like it – it has the Hari Seldon who’d hoped to finish Psychohistory by now gradually realizing it’ll take him the rest of his life, and even that might not be enough.
    (I figure “fictional super-mathematician” is still probably the best person to be reminiscent of on your birthday)

  9. ike Says:

    happy birthday! rest assured, there’s people out there slowly approaching their forties that haven’t delivered a fraction of your output. also: 30 is the new 20. which means 40 is the new 30!

  10. Adam Chalmers Says:

    Happy birthday Scott! When we met, I already expected your intelligence, but I was really surprised that your intelligence was matched by your kindness. I really appreciated you and Dana opening your house to me when I was new to the USA, especially being able to have a Pesach seder my first year away from all my friends and family. Watching you meet someone for the first time is always really fun, because you seem so genuinely interested in every new person you meet. I hope this takes you far in life, and that your next 40 years are even better than your first 40 years.

  11. Shaked Koplewitz Says:

    @Paul Hoffman #7 someone already tried to solve the Israeli-Palestinian conflict using quantum superpositioning (https://unsongbook.com/chapter-36-my-fathers-business/). It didn’t work out that well in the long term

  12. Benoit Essiambre Says:

    I’ve been reading your blog since pretty much the beginning (16 years ago!) even sometimes vaguely understanding small discrete amounts of the quantum world. I enjoyed every word of it. I never realized we were so close in age. I turned 40 less than two months ago. Happy Birthday!

  13. mjgeddes Says:

    Well, by having a blog to try to explain science to the public, you’re making reality more comprehensible, which ‘boosts the measure of existence’. Agents are ‘creating the computational layer of reality’ when they create new knowledge, and here, you are certainly doing better than most. Only continuous knowledge creation that exceeds a critical rate can enable one to achieve ‘longevity escape velocity’, using the arrow of ‘logical time’ (or ‘compositional time’) to beat the arrow of ‘physical time’ (ordinary physical ‘causality’).

    I hope you still look into Wolfram. They do have a very smart researcher in Jonathan Gorard, and I think recent Wolfram posts are definite improvements on earlier ones. You know, old Wolfram may not actually be too far away from getting somewhere now, he’s kind of hovering around the edges of real insights I think. The mistake he’s making, I think, is to try to reduce all of reality to computation, which won’t work. I’m now reasonably sure that computation is an emergent layer, whereas physics and math are primary. I’m skeptical that they’ll get any where on the physics stuff (certainly not quantum gravity), but the math ideas might be worth looking at. Category theory (and computational models in general) probably doesn’t have anything to do with relativity or quantum mechanics, but it just *might* have something to do with *statistical mechanics* !

    The evolution of an individual life mirrors that of the computational layer of reality itself. Continuous knowledge creation is the arrow of ‘logical time’, in a race with the increase in entropy given by ‘physical time’. Only the advance of logical time can complete the construction of reality. Should it fail to exceed the rate of physical time, nascent reality will crash back into the goo of ‘possible worlds’ from whence it came. And so too with individual conscious minds.

  14. Dylan Langone Says:

    Happy Birthday!! It has been nothing other than a pleasure reading both your blog and your book over the past year. There are a select few who write as well as you about anything. If I could I would nominate you for a Nobel Prize in Literature.

  15. Russell Graham Impagliazzo Says:

    It’s so cute when you kids talk about “getting old”. Happy birthday!

  16. Adam B Says:

    Happy Birthday! Your blog has been an inspiration to me for years.

  17. Zeb Says:

    Happy Birthday! I really enjoyed your book Quantum Computing Since Democritus (the argument against Bohmian mechanics is the part of that book that stuck out the most in my memory – I found it completely convincing). I also have to admit that I rely on your blog for news on quantum computing and breakthroughs in computer science more generally.

  18. Ben Says:

    Welcome to the 40th club! An epic milestone, one to reflect and make sure the last 40 or so years left is worthwhile for the time & energy you spend on projects & people. God speed

  19. Ryan Alweiss Says:

    Happy Birthday Scott! Your blog is absolutely fantastic, and you are a voice of reason on many many issues. You stand up for the values we should all believe in (including of course quantum supremacy).

  20. Doug K Says:

    happy birthday !

    like Daniel I mostly lurk but read and enjoy (as far as my comprehension stretches) all you write – thank you..

    I got over my midlife/achievement crisis early, after a major depressive episode probably linked to a lived experience like comment 171, a stint in the army, and surviving an assault or two: after that just being alive and able to earn a living seemed achievement enough..

  21. Jim Kukula Says:

    My years before I was 40 pretty well set my direction, but now I am 65… most of my more significant accomplishments were after I turned 40!

    Keep up all the great work! You’re a real inspiration!

  22. James Gallagher Says:

    Happy Birthday Scott.

    You are a remarkably tolerant person, in an increasingly hostile world.

    If you couldn’t enjoy the day, don’t worry you have your 15000 day “birthday” to look forward to next June…

  23. Jeremy Says:

    Happy 40th Scott! Thanks for always answering questions from the plebeians in your comment section like me :).

  24. Florian Says:

    Happy birthday Scott. Long-time reader, first-time poster. You can be extremely proud of what you’ve achieved in those forty years. Don’t be sad about what you haven’t achieved but celebrate what you have. There is absolutely no point in the former and in your case a lot to admire in the latter. Compared to any average human being you have an exceptional mind and you have inspired thousands of younger people to follow in your food steps. You’ve literally made the world a better place. So stop whining and be happy, you owe it to your creator.

  25. Bram Cohen Says:

    Hey Scott, if it makes you feel any better having all those half-finished projects means that all you need to do to be productive for years if not decades to come is pick up those projects and do them. Also if it makes you feel any better most of the ‘real’ math I’ve done has been in my 40s but at age 45 I’m worried that I simply won’t be able to live up to the expectations I’ve set in the past, both as an engineer and puzzle inventor, and all I have left to do now is flesh out the projects I’ve started already. On the other hand the chances of actually finishing those before entropy takes its toll on my mortal body seem vanishingly small, so perhaps all is not lost.

  26. Ashley Says:

    Happy Birthday Scott!

    When I turned 40 couple of a few years back my Mom wished me saying (roughly translated) that it is the age of wisdom. I do think it is.

    And thank you, very much, for the “more than a third of the years”.

  27. Ronald de Wolf Says:

    I remember when you were young. You shone like the sun (Pink Floyd reference intended), but you’re a much more complete person now

  28. Ken Miller Says:

    Happy birthday! I enjoyed meeting you some years back at sci-foo, and running the workshop with you on whether brains could be uploaded (or something like that). It was the highlight for me, and the thing that first comes to mind when I think about the conference. Who knew I would become the writer of long and possibly irritating comments about Israel and Gaza on your blog? “^) Anyhow I always find your blog stimulating and when I check feedly generally look first to see if there’s anything new from you.

    As for getting older — it doesn’t stop, it only goes faster. You crash through 40, then 50, then 60, and so on, all ages that seemed impossibly old till you got to them. Each one more surprising than the last. Until of course one day you are not there any more. As the oldest woman known, who lived to be 122, said at one point, “I’m still a young girl, I just haven’t looked too good for the last 70 years”. I think the Buddhists have got it right — the delusion that causes suffering is the sense that things are eternal, and the attempts to hold onto them as they inevitably change or disappear; and freedom and an end to suffering, at least of some kinds, comes from acceptance, experiencing fully while accepting the transience of all things including yourself, your ego, your consciousness, not holding on to them, not attaching to them. The opposite of attached is not detached, it is acceptance. Not that I’ve achieved any of that. But the older you get and the more real the transience of all this becomes, the more you have to wrestle with how to find meaning in the face of that. Anyhow, may you keep looking good for the next 70 years!

  29. Job Says:

    I’m only a few months behind you, so I am curious.

    At 40, is that when we’re granted collective control over the world?

    Is there a secret ritual we don’t know about? Maybe, where we’re told what’s going on and how to operate reality?

    I am expecting a ceremony, certainly. And transfer of power.

  30. Richard Gaylord Says:

    “Stephen Wolfram’s recrudescent claims of a unified theory of physics.”. Why do you say that his claim is recrudescent (btw – nice word; i had to look up its meaning)? His hypergraph approach is new; it’s not mentioned in his NKS book. note: it is not clear that Wolfram even has a theory of physics since it fails the basic falsifiability requirement of a scientific theory (see https://www.forbes.com/sites/startswithabang/2020/05/13/3-simple-reasons-why-wolframs-new-fundamental-theory-is-not-yet-science/?sh=6adbb62413a1) as he points out (“Any particular rule could be proved wrong by disagreeing with observations, for example predicting particles that do not exist. But the overall framework of our models is something more general, and not as directly amenable to experimental falsification. Asking how to falsify our framework is similar to asking how one would prove that calculus could not be a model for physics. An obvious answer would be another model successfully providing a fundamental theory of physics, and being proved incompatible.”

  31. Richard Gaylord Says:

    mjgeddes #13 – you say that “computation is an emergent layer, whereas physics and math are primary.” can you explicate this statement? math (or ‘maths’ as they say in England) can either be a subject or a tool for studying a subject (such as physics) while physics is a subject rather than a tool.

  32. Jim Hefferon Says:

    Thank you for giving the keynote address at the 2016 Hudson River Undergraduate Math Research Conference, which I helped organize. It was one of the best keynotes ever in that venue, and a most gracious visit. Happy Birthday.

  33. Jr Says:

    Happy arbitrary numerical milestone!

    I have found your posts on theoretical computer science a real eye-opener and they have made me strongly appreciative of the mathematical value of that field.

    Your posts on other issues have always struck me as showing a rare common sense and wisdom.

  34. LK2 Says:

    Dear Scott: happy birthday!!!
    In this occasion I wanted just to share this: when I was a young student studying physics, I encountered a strange book called “Algorithms and Data Structures”. The first chapter talked about P, NP, NP completeness and Turing machines: it was a revelation for me! But how to study all those great things? I did not know, and nobody around me knew. So I went on to end up with a phd in physics and somewhat forgetting the “discovery” of computability and complexity which made so much sense to me as interpretation of the physical universe. Then towards the end on the Phd I made another discovery: Shtetl Optimized! This revamped my interest in TCS, I bought your book, the one of Boaz Barak and QC stuff…So actually you made me a present with your excellent outreach activity!
    I have a couple of years more that you and I still do not fell old, so do not worry 😉
    All the best, Scott!

  35. pessimist Says:

    Scott, happy birthday! What you’ve accomplished at 40 is more than 99.99% of us have at older ages and I’m sure the best is to come.Thanks for the blog – it continues to provide for me a vicarious experience of math, physics and cs research – that is, what I wish I was doing instead of the crappy corp job that I’m actually stuck with!

  36. Berkeley Professor Says:

    Youth is overrated. We’ve become a shallow culture that fetishizes youth since about the 1960’s, but it was wrong then and it’s wrong now. Civilization is run by people 45-70 for good reasons.

    I’m much more fulfilled at 52 than I was at 40. More importantly, I feel like I understand the world a bit now, and I can’t believe how clueless I was at 40. One gift of age is being able to see patterns in our world that take 20-40 years of adult observation to recognize. While I can’t say I’ve done my most popular work since 40, I’ve certainly proven my most difficult theorems by far in that time, and I feel I’m still getting stronger. I bet you can look forward to the same.

    Happy 40th birthday, Scott, and thanks for your amazing blog! I still don’t know any quantum computing, though, so I’ll have to single out your paper “Is P Versus NP Formally Independent?” and your post on “Rosser’s Theorem via Turing machines” as the times you’ve given me the most joy.

  37. Sonya Says:

    Happy Birthday! I find the universality of the feeling that one has not accomplished what one should by X age to be oddly reassuring. To look at it from another perspective – fellow survivor of Council Rock in the mid-90s, we have indeed survived, and well.

  38. Roger Says:

    I enjoy your blog. The biggest selling nonfiction book of 1933 was Life Begins at Forty.

  39. Jelmer Renema Says:

    Happy birthday! I was reminded by your post of this: https://www.smbc-comics.com/comic/2010-03-27

  40. 1Zer0 Says:

    Happy Birthday Scott! I regard your blog as the best when it comes to interdisciplinary connecting branches of philosophy, mathematics and computer science.

  41. Nick Says:

    Looks like you’ll never get that Fields medal you always dreamed of. On the other hand, they say that the prophet Muhammad (PBUH) was forty years old when he received his first revelation. Similarly, Donald Knuth (PBUH) started implementing TeX at age forty. So there’s still plenty to do.

  42. Pavlos Says:

    Happy Birthday!!!!!!!!!!!! ???????????????????????? Scott, we love you man!!!!

    Please drop everything else and do just AdS/CFT, the children’s book and the blog! ????

    I have been reading your posts for years and, as everybody knows, it’s amazing. But the post that has had the greatest (hopefully positive ????) influence on me was the recent “part one” about the Continuum Hypothesis. It gave me a big push towards the solution of a problem i had been working on for years. (I am maniacally refreshing for part 2 since ????)

    Thank you so much for all this great writing! You are an amazing scientist. Make the next decade the best yet, the world needs people like you.

  43. Mary Says:

    I discovered this lovely gem while searching for Big Ideas in science, to include in a curriculum for a multidisciplinary summer school which led me to a debate on falsifiability which led me to
    the essay ‘Who Can Name the Bigger Number?’ and here I am, scrolling through insights and observations that teleport me into another dimension. Dear Scott, professor Scott, not having accomplished what you wanted in your thirties and still having accomplished so many meaningful things by now is the best combination one can aspire to have.
    I am looking forward to the graphic novel about teaching math!
    An anonymous 36-year-old comms grad from Romania living in Glasgow who’s just discovered this and felt the impulse to leave her first comment on a blog.

  44. Raza Syed Abbas Says:

    You have taught me much over the years, Scott, though you are 17 years younger than me. So thank you, and happy birthday! May you have many more. 🙂

  45. Lön Says:

    Happy Birthday, Scott!
    I really enjoy reading your blog and I am impressed by the honesty in your writing. To many more thought-provoking years! 🙂

  46. Jay Says:

    Happy birthday! As many you made me understand how important (and fun) CS is, plus I was fascinated by your proposal for freebits. Thanks for your candor in explaining your inner life as a nerd. We all saw the kind of rudness you had to endure for it. Let’s call that « taking one for the team », the team of all who want a better future for both our daughters and fellow nerds. I can’t wait to see what you’ll do the next fourties. 🙂

  47. John Stricker Says:

    Dear Scott, congratulations on your 40th birthday! Don´t worry, 40 is the new 20, so there is still plenty of time for everything ;-).

    On to the next 40 years!

  48. 1Zer0 Says:

    Second comment, I think it fits here as well, since the post is also tagged “self-referential” after all and this (Not perfect but overall pretty good) video on Gödel’s Incompleteness Theorems was just released a few hours ago by a large science youtuber.
    I like how it’s emphasized that self reference and diagonalization are at the heart of the Incompleteness Theorems.
    It also includes a reference to the Spectral Gap problem, but I don’t think he emphasized enough that it doesn’t concern as you put it in this https://scottaaronson-production.mystagingwebsite.com/?p=2586 blogpost ” …the result does not say—or even suggest—that there’s any real, finite physical system whose behavior is Gödel- or Turing-undecidable.”

  49. HasH Says:

    Happy Birthday Brother,

    You are in my Top 10 Jew I love List almost 2 years now. Watched almost every video on YouTube. “Live long and prosper” brother, My money’s on you (even i don’t believe/have earthly possession)!

    High Love from Overseas!

  50. Julien Says:

    Happy birthday Scott!
    Glad to have shared 9/10 of that time in the same branch of the wave function as you!

  51. Qiaochu Yuan Says:

    Happy birhday Scott! I don’t know if this is a memory you’ll particularly enjoy being brought back to, but I continue to be really moved by all of the stuff that happened around comment 171, especially the other Scott coming so passionately to your defense. I’ve had my own struggles with masculinity and gender relations and so forth and seeing all that stuff out in the open on the internet from two of my favorite bloggers was a really eye-opening and formative experience for me (although seeing the blowback from everyone else made me really scared to talk about it for awhile too so, uh…). Getting to hear about all the feedback you got in private in the follow-up post was really eye-opening too.

    I also really enjoyed the talk you gave at SPARC about common knowledge! It sparked a lot of fun thoughts for me and I’m sure the students enjoyed it a lot too.

  52. Michael Ball Says:

    Hi Scott. Happy 40th!

    I have been reading your blog for almost 5 years; though I rarely comment. I have learnt a lot about complexity and quantum computing from both your blog and QCSD.

    On a more personal level, I really appreciate you sharing details of your struggles growing up. Much of what you wrote resonates with me. Your professional and personal successes give me hope that things can improve in my life (though you were much younger than me when things started to fall into place for you). I find the clarity, precision, reason, honesty and sometimes bravery (comment #171) with which you write to be truly refreshing.

    Keep doing what your doing. You are a force for good in the world.

    And write that post on the Continuum Hypothesis!

  53. Julian DCosta Says:

    Happy birthday Scott!

    Over the years, I’ve really enjoyed reading your blog, QCSD, and expository essays, which were always incredibly entertaining even when I didn’t understand them.

    Also we’ve met briefly in person and you were super nice 🙂

    Something you said once that stuck with me – you wrote
    “For a writer, I can think of no higher aspiration than that: to write like Bertrand Russell or like Scott Alexander—in such a way that, even when people quote you to stand above you, your words break free of the imprisoning quotation marks, wiggle past the critics, and enter the minds of readers of your generation and of generations not yet born.”

    I think that’s a remarkably beautiful idea, and your phrasing of it will always live in my head.
    Good luck for the next forty and beyond!

  54. Scott Says:

    Nick #41:

      they say that the prophet Muhammad (PBUH) was forty years old when he received his first revelation

    Good point. Moses was also 40 when God spoke to him from the burning bush. On the other hand, by the time Jesus was my age, He’d already been crucified for 7 years. No matter how you look at it, time to get moving! 🙂

  55. JimV Says:

    Well, I did most of my best work on engineering and computer games after 40, albeit while complaining that I was steadily losing IQ points (whatever they are), mainly I think due to loss of speed of memory. If you can’t remember stuff you need when you need it, you make a bunch of mistakes that seem stupid the moment after you make them.

    But if you’ve kept notes and files, on a lot of problems you can just use something you figured out long ago, so your work productivity goes up from that as it goes down from the other.

    I haven’t always agreed with what you wrote here (although mostly), but I’ve always admired the way you wrote it. A couple times I’ve suggested you publish a book of essays taken from your blog posts, and I still think that would benefit a lot of readers who don’t read blogs, but with all the other projects you want to finish, I can see why that hasn’t happened.

    As for accomplishments, if I had a fifth of yours I would die content. (Or maybe I would always want more, as you do. Can’t blame us for that.)

  56. JimV Says:

    P.S. A rule about presentations that served me well when I remembered to practice it: always rehearse beforehand in as close to the actual venue/conditions as possible.

    I learned that from my friend Mario (he had won a Golden Gavel at the annular Effective Presentation contest). He told me he practiced his speeches in front of a mirror. For his last presentation he had asked me to print out a banner on computer paper (the old continuous kind, with the letters in landscape mode, almost as high as the pages were wide, saying OXIDATION, which was the punchline to his presentation, across several pages). When he held it up at the end, with the lettered side facing outwards, he had it upside down. The other thing that happens as you get older (he was in his early 60’s) is that you stop doing all the finicky checks, because you’ve done this 1000 times before, or something. (Or maybe he got the 50-50 chance right when he rehearsed in front of the mirror, if he actually did.) (Should have had an up-arrow on the back of the paper. I didn’t think of it either.)

    I could tell you about some of my presentation problems, but they’re classified. Yes, even the Valedictorian speech I screwed up. (That class on Effective Presentation at GE which I didn’t want to take did me a lot of good.)

  57. Job Says:

    Moses was also 40 when God appeared to him in the burning bush.

    Wait, so that’s the transfer-of-power ritual that happens when you reach 40?

    A burning bush isn’t much of a ceremony, I was expecting something grander.
    But i guess it’s supposed to be a secretive thing.

    I’ll try to appear surprised.

  58. Boaz Barak Says:

    Happy birthday Scott!

    There’s much I can say but I’ll just mention that I still have about 5-10 copies of QCSD that I hope to go back soon to giving out to smart and curious students.

    In more innocent times I used to say that QCSD is the best vector to “infect” young minds with the “TCS bug”

  59. jonas Says:

    Happy birthday, Scott.

    I hope that your book and blog inspired someone to a carrier in mathematics. You are too young to have done that to me, but there’s always a younger generation.

  60. Fnord Says:


    I actually spent quite some time thinking about what to post here. I went back and forth over several aspects on why I read your blog, what I think about you, how that relates to me and so on.

    But ultimately, I believe it’s best if I just write: “I respect you.” Because I do.

    May your past life have been the worst of your days.

  61. Shmi Says:

    Scott, to be fair, you were crucified at 33 for the comment 171, yet miraculously survived. Though the analogy stops there, I suppose.

    40 is not a terrible age, I started my PhD at 40, and managed to learn a few things along the way, and write a bit about black holes in various dimensions.

    My favorite piece of your popular writing remains the one I posted a review of at some point, TGITQM, and I often tell people to read section 2 whenever they start talking about free will.

    Happy birthday, and may your argument with Gil Kalai be settled experimentally before your next big anniversary. That, or peace in the Middle East, whichever is more likely.

  62. Scott Says:

    Shmi #61:

      Scott, to be fair, you were crucified at 33 for the comment 171, yet miraculously survived…

    Verily I say unto thee, that all ye who believed in me even as I was crucified, ye have earned thy place in the Kingdom of BQP. 😉

  63. mjgeddes Says:

    Richard #31,

    I meant for the purposes of metaphysics, it’s very useful to separate reality into 3 layers, which can be ordered in terms of a level of abstraction: objects that aren’t in space and time (mathematical objects), objects which are in time but not space (computational objects). and objects that are in both time and space (physical objects).

    It’s really not clear how something like the Wolfram project can work, because computational models seem too general to provide much insight into the specifics of physics.

    But philosophizing on the nature of time has made me suspect that we are in an unusual metaphysical situation, and we are in fact, not fully ‘real’ ! 😀 At least, not yet. So, my increasing suspicion is that the reality we know has not been fully ‘actualized’ or constructed yet. It’s not that we’re in a simulation exactly, but nor are we fully ‘real’ now. We’re sort of in a ‘half-way house’ reality, poised mid-way between purely symbolic existence, and fully ‘actualized’ existence. Simulation purgatory? 😉

    In any event, I think our reality can still ‘crash’, it can wink out of existence, just as we as individuals can. And it’s all hinging on that computational layer. Only a super-intelligence can complete the construction, rescind aging and death, and fully ‘actualize’ existence, finally granting us the status of being fully ‘real’.

    I mean, for computation, there is something physical, but seems like part of it is also subjectively created by us. So the objects of computer science are not quite as solid as physics.

    Or in plain English, time be a flying, so make the most of it while it lasts!

  64. asdf Says:

    Scott, you’re fine. You turned 40 the day after your 35th birthday, because that put you in your late thirties, which is basically an alias for early forties. Before that you were in your early thirties, which is another way of saying late twenties. That means you age 20 years in one day.

    Turning 40 is just reaching a number on an odometer. Turning 35 is actually tough, and it shows up in your blood proteins:


    Anyway, here, put on some music: https://www.youtube.com/watch?v=Re4C33thTEE

  65. Luca Says:

    Happy birthday. Reading your book QCsD and your papers has been a truly mind-opening experience. Thanks.

  66. Rashid Al-Heidous Says:

    Happy Birthday Scott,

    I believe that the quest for “good” life is a qualitative and not quantitative one. It’s not how long you live but how fulfilling your life is, how can you make every remaining moment counts, to say at the end: “That was quite the journey I had. It was genuinly fun to be alive!”

    I am just a passerby who is facsinated by Quantum computing and aspire to contribute to the field soon enough. Hope to meet you one day and have a good chat about Quantum science!

    Cheers 🙂

  67. Andrew Krause Says:

    I’ve always really appreciated numerous things about your blog, but perhaps most importantly your compassion, and to a lesser degree, your infectious curiosity. I started reading here since undergrad, and it has been enormously helpful to follow along, even as I drifted from CS into Applied Math.

    I start a permanent faculty gig in the Fall. I hope I can be even half as kind and sharing of my knowledge as you have been!

  68. JoshP Says:

    If Newton had internet access we wouldn’t have Principia.

  69. gentzen Says:

    Happy birthday!

    Your fight against alternative facts started long ago, when nobody could yet have predicted the last four years. You called science journalism to order, and offered your time to enable more accurate reporting. So you didn’t just raise the awareness, but you also made it easier not to be wrong. Just like your complexity zoo before enabled everybody including beginners and interdisciplinary researchers to be less stupid. You defended common sense and reason against anonymous with replies like “As a firm believer in science and reason, I strive to distinguish clearly between what I can prove and what I merely know is true.” in Reasons to believe. This made it easier for everybody to express what they knew (me included). It is not important whether this explicitly expressed knowledge contributes to progress or not, the mere fact to not be forced to keep silent about what you know feels good. But back to the last four years. Your courage to face the dark times, to accept the comments of the other side, to engage with them, to warn about what would happen next, to ensure that common knowledge really became common knowledge, all that was extremely helpful for me. It enabled me to reply to those (close to me) that were sympathetic to what happened that they just don’t know enough about the US, just like I don’t know enough about Russia. They told me that Biden is too old and has dementia. I replied that he is the same age as my mother and that she would definitively not be too old. She was delighted.

  70. Another Scott Says:

    Found your blog early on in college. I think you are the first academic blog I actually read. You’ve since been the role model for how good science communication, and good internet citizenship, should look.

    It’s a really special thing seeing a professional hold office hours in the comments for so many people. There’s too many little question and answer sessions you’ve done in the comments to quote specifics. I don’t ask much, but listening to others questions was always a favorite past time.

    It’s an extra special thing to see how you prioritize and promote various social good. So much of engineering schools put up a wall between current policy and events.

    Happy birthday, and thank you.

  71. Rahul Nandkishore Says:

    Happy birthday Scott! I’ve been reading your blog ever since I was a graduate student (though this is my first time commenting). It’s been my main source of understanding for the CS end of quantum computation, so thank you for your always clear exposition. And it was through your blog that I discovered Scott Alexander, so thank you for that also. 🙂

  72. Eitan Bachmat Says:

    Dear Scott
    Congratulations on your
    second order phase transition
    Everything you wrote on the
    blog did and meant so much to me

  73. Peter S. Shenkin Says:

    Gee, I wanna hear about the coffee and cream.

    For instance, should you add the cream to the coffee or the coffee to the cream? (Assuming the coffee is hot and the cream is cool.)

    The question is usually asked with tea, but it’s the same answer.

    This was posed to me by my (chemistry) dissertation advisor, and I believe his answer was right. But I’ve seen others opine to the contrary, despite recognizing the underlying science. But that just goes to show that you can be wrong for the right reason.

  74. wolfgang Says:

    Happy Birthday!

    I really like your blog – that’s all I have to say about that 😎

  75. Filip Dimitrovski Says:

    Happy birthday ????
    If you have a mid-life crisis in some future, would you rather buy a motorbike or attempt some crazy Computer Science idea?

  76. John Stricker Says:

    Forgot your present: I greatly appreciate your ability to explain difficult mathematical concepts, as well as your undefeatable personal honesty and integrity.

  77. Vanessa Says:

    Dear Scott,

    Thank you for being a voice for sanity, compassion and moderation in a world which sometimes seem bent on taking everything to the craziest imaginable extreme. *And* a great source of quantum computing news for non-specialists. Happy birthday!

  78. Doug Says:

    > If you feel compelled to give me a 40th birthday present, then just make it a comment on this post, as short or long as you like, about what anything I said or did meant for you. I’m a total softie for that stuff.

    Alan Turing, Moralist meant quite a lot to me. This is a powerful moral challenge. Whatever technical discussions we may be inclined to have, the bedrock question is, “How should we treat others?” It has stuck with me well. So thank you!

    Happy Birthday, and many happy returns!

  79. Rahul Santhanam Says:

    Happy Birthday Scott!

    I love this blog for the wise comments it attracts. This is especially the case for posts tagged “Self-Referential”.

  80. Camilo Says:

    Dear Scott,

    This is the first time I comment here, even though I have read your blog for more than 10 years.
    Shtetl Optimized is a part of my routine, where I come back in search for thoughtful ideas on computation, math and physics, and good faith opinions about the state of the world. Reading your book QCSD was a very joyful experience for me, in a time where joy was scarce.
    It surprises me how personal this message came out, given that we have never met and you don’t know I exist, but that is how it feels to me. Internet is amazing.

    Best wishes and Congratulations from Colombia!

  81. Aspect Says:

    Hi Scott,

    (I understand this post is a bit of a cliche so bear with me. I’ve been meaning to write you an email for a while, but I guess writing here is fine too.)

    I grew up in a small town, without any aspirations of doing anything related to academia whatsoever. There was no such expectation from my family either. I wasn’t particularly drawn to science or math. I just played video games. I was comfortable dealing with computers, and I was OK in school without having to put much effort… but that’s about it.
    Everyone within a few degrees of separation from me had at most an undergrad education. That’s considered a success in my town. Doing anything more than that never really crossed my mind. It looked like all this stuff was reserved for the extremely talented geniuses that have demonstrated a very high aptitude for math and science since early on in their lives .

    Anyway, I found your blog a little over a decade ago when I was still a teenager. I remember not following the technical arguments you were making. I don’t remember what the first post I saw was, but I remember you were in the trenches passionately arguing about something 😀
    I think I didn’t sleep much that night because I was absorbed by the exchanges you guys were having in the comments. Even though I couldn’t follow the technical parts, the way you were talking made a lot of sense to me. For some reason, I could follow the “high-level outlines” of the arguments despite not grasping the mathematical content in detail.

    I kind of started wondering how I was able to follow at all… You guys were supposed to be ivory tower wizards, far beyond “mere mortals” like me. One day I noticed someone asking a bit of a naive question in the comments. Despite my limited knowledge, I could tell that the question was more or less misguided. To my surprise, I saw you engage with that person and legitimately try to reason with them, try to help them understand, all while being totally casual about it and using common internet acronyms/lingo. You were eager to engage with anybody, no matter how silly they sounded. You tried to make a convincing case regardless of who was behind the random internet username you were responding to. Maybe it sounds weird, but my views about people like you (and higher education in general) were so twisted that it was hard to believe that you could behave the way you did.

    To make a long story short, in some sense the blog was my primary connection to the academic world. I went to uni for CS. I still was OK at it, passing classes without too much trouble but not really devoting any significant effort to develop a deep understanding of the material or to get good grades. I read QCSD when it came out. In those years I also picked up other books like Deutsch’s Fabric of Reality and GEB. Having read all that stuff, I started finding the connections between my intuition/curiosity and various technical subjects. Slowly, the technical content in your blog started to make more sense too. I started taking university more seriously as well. Over the next few years, my understanding of the world changed dramatically.

    I will skip the rest of the details. The important thing is that now I’m in another country, doing my PhD on a subject that I find very interesting, at a place that has a lot of great/smart/talented people. Things are going well (OK apart from the global pandemic of course). My first paper also did very well; much better than I expected.

    That’s why I am here now. I just wanted to say thanks, and happy birthday. Seeing you just write stuff here on this blog over the years has played a significant part in my life. I am really grateful for everything that you’ve done, be it the blog, the book, or the talks that you’ve given. I still have a lot of catching up to do, but these days I can understand the technical content of your arguments just as well as the “high-level outlines”. 😀

  82. Robert Chew Says:

    Happy Birthday, Prof! You have accomplished far more than 99.99999% of the rest of us.

    Surely, DOD should not be bothered by 10 mins of distraction. Life is far too important to be easily impacted.

  83. Michel Says:

    Congratulations Scott,
    But 40 is not old:
    70 years are mine, is told
    but I am now studying Quantum CS
    and that is all your fault…

  84. Felipe Pait Says:

    The list of unfinished projects resonated with me. Although I’ve been a professor for more than half of my life, I still have many of those. The gentle optimism of your post encourages me to keep working on them….. All the best!

  85. Jonathan Says:

    Happy birthday Scott!

    I was just watching the video of you in the AstralCodexTen meetup and noticed the mic quality really isn’t the best, might I offer to order you a USB mic as a gift or else send some suggestions over?

    Video link for others curious: https://www.youtube.com/watch?v=DEYUt1tJlck

  86. Edan Maor Says:

    Happy birthday Scott!

    Your posts have been one of my most consistent sources of interest and inspiration when it comes to math and Computer Science (and, relatedly, one of my largest sources of feeling like I haven’t achieved what *I* wanted, or that I should’ve gone down the academic path instead of software engineering / entrepreneurship!).

    I didn’t catch your Israel-Palestine post in time to say this there, but you are an amazingly sane voice on the topic, and on many other topics, and the fact that my beliefs closely align with yours on many things is one thing that reassures me that I’m not crazy and that my beliefs are likely correct (and moral!).

    Thank you for all that you’ve already given the world Scott, and please continue for many many more years! 🙂

  87. Chris Says:

    Happy birthday Scott!

    It was reading (and re-reading) QCSD that finally convinced me to take the plunge and pursue a PhD in quantum computing, despite the formidably steep learning curve that stood before me, having never had much formal math training (I had what was essentially an undergraduate degree in software engineering).

    It was reading this blog that often gave, and still very much gives, me the energy to keep dragging myself up this curve. I still have a huge way to go, but I’m incredibly happy with where I am, and for the part you’ve played in that: Thank you!

  88. Bill Kaminsky Says:

    Happy Belated 40th Birthday, Scott!

    Since today (i.e., May 24, 2021) happens to Bob Dylan’s 80th birthday, I think the following lyric of Dylan is germane:

    In a soldier’s stance, I aimed my hand

    At the mongrel dogs who teach

    Fearing not that I’d become my enemy

    In the instant that I preach

    My pathway led by confusion boats

    Mutiny from stern to bow

    Ah, but I was so much older then

    I’m younger than that now

    — Penultimate verse of “My Back Pages” (1964)

    I offer Dylan’s lyric in the following spirit. Yes, “Doofosity” (to quote my favorite blog topic tag of yours) is quite arguably the crucial factor in world affairs that will decide whether we and our progeny all shall get to develop ourselves further or whether we all shall just destroy ourselves and their possibilities utterly. Nonetheless, I contend that — especially, as one ages — one must move from the “Rage Against Doofosity” to as “Assiduous-but-wisely-Calm Campaign Against Doofosity”. 😉

  89. John Preskill Says:

    A good start.

  90. Daniel Suo Says:


    Long-time reader (and now working with Elad Hazan at Google Princeton and sitting next to Xinyi!) who enjoys all your posts, but only no now prompted to emerge from lurker-status. (But only for a comment. Like the cicadas amongst us, I shall crawl back under ground now).

    Especially enjoyed your last post regarding the conflict…enlightening for a layperson.

    Thanks for the continuous effort and Happy Birthday!!


  91. barbara Says:

    Dear Scott, although I am late – my best whishes to your 28th birthday, which looks less terrific in hex, hence no need to panic about this particular date. Reading your blog reopend the door to the realms of theory, I had to close during my PhD studies on wireless networks. Thank you for redescovering the magic of complexity theory :). Moreover I owe you much for sharing your ideas on quantum computing, a big thank you for this, too.

  92. HasH Says:

    I keep coming back to read comments 🙂

  93. Colin Rosenthal Says:

    Congratulations on the milestone/millstone! Now what fraction of that 40 years have you spent writing a blog-series on the Independence Of The Continuum Hypothesis?

  94. Stephen Jordan Says:

    Collectively, your blog posts in the early 2000s and your PhD thesis (via the arxiv) were an influence for me to become interested in quantum algorithms and complexity theory. On the whole I think this life path has turned out better for me than my most likely alternative, namely working on the theory of high temperature superconductivity.

  95. Umut Isik Says:

    Scott, your book and lectures motivated me to finally get into computational complexity ‘for real’ as a research area and helped me make my own path in math — work I am proud of. I am no longer in math but with no regrets thanks to that. Happy birthday and best wishes.

  96. Lijie Says:

    Happy birthday Scott! (I am a bit late)

    Your book on QCSD led me to the world of quantum computing and complexity theory and I still reread it very often. I really learned a lot from you during my semester-long visit at MIT (can’t believe it has been 5 years!), it had a tremendous influence on me.

  97. Don M Says:

    Happy 40th Scott. That’s almost adolescent, from my perspective. My biggest achievements came after that. Raised a child (well, she raised herself, but that’s another story), got PhD at 50, trekked to Mt Everest Base Camp for my 70th bday, as a lifelong klutz who was laughed off the high-school basketball team and couldn’t ride a two-wheeler until I was 8. You have way more things to do that you’re good and great at, and more things to do that you have no idea yet that you’ll be good at.

    PS: before 80, I want to give QCSD another shot to get more than 50%…

  98. Ashley Lopez Says:

    John Preskill #89:

    That was very inspiring (for us 40+ year olds)!! Thank you.

  99. Andrew Knight Says:

    Hi Scott… I realized that my last email to you (on why QC is not scalable) was sent on your birthday… and now I feel like a real ass. Since you are a “softie” for hearing about how something you said/did was meaningful (I think we all want to feel like we are meaningful in the world)… I’ll say that your Ghost in the Quantum Turing Machine is probably the most influential thing I’ve read in the past decade, behind only Penrose’s Emperor’s New Mind. You clearly and creatively addressed some of the hardest and most important questions in the foundations of physics and the philosophy of physics. So few people in the hard sciences muse on these topics (at least in published papers/books), and it was (and remains) refreshing to reflect on your thoughts. Thank you for writing it.

  100. Gil Kalai Says:

    Happy birthday, Scott! מזל טוב

  101. Cem Say Says:

    Happy birthday, Scott!

    Thank you for the really huge educational effort that is this blog, by the way. It is a great accomplishment, and has been enormously useful to me and many other people.

  102. Mingi Says:

    Happy birthday Scott! Don’t worry too much about the past or age for that matter, you still have +2K weeks to achieve everything you hoped for and much more.

  103. Julio Cesar JX Says:

    Happy Birthday Dr. Aaronson; you are a inspiration, without your blog I could not be aware of amazing topics like complexity and quantum computing. Now thanks to you Im in the road to be a quantum scientist. Greetings from Mexico and enjoy the large amount of years that will come

  104. Elad Hazan Says:

    Mazal Tov Scott!
    You asked for a favorite: one of the nicest blog posts I’ve ever read was one about “naming the largest number”, I forget if it’s a blog post or article… Anyways, I recall reading it and being inspired to go to grad school, so thanks!! 🙂

  105. Aaron G Says:

    Happy Birthday!

    For what it’s worth, I do not consider 40 to be on the “old side” of life. I consider age 50 to be that milestone.

    Granted, I’m 45 (turning 46 this year) so admittedly I’m somewhat biased! 😉

  106. Rand Says:

    >> If you feel compelled to give me a 40th birthday present, then just make it a comment on this post, as short or long as you like, about what anything I said or did meant for you. I’m a total softie for that stuff.

    Well, let’s see.

    – I’ve been reading this blog since I was an undergraduate (2007-2011).
    – When the Yeshiva University CS club invited me to give a talk about the philosophical implications of CS research, I asked them if they could try to bring in Scott Aaronson who is a professor who thinks about this stuff and is “way cooler than me”. The talk was great, as was chatting afterwards.
    – The first time I ever went to therapy, I told the therapist that I wanted to become a professor so I could teach a course like Quantum Computing Since Democritus (and write a blog like this one).
    – I asked Penn to order digital and physical copies of the book the day it came out and read through it while taking a class on randomized algorithms.
    – You gave a keynote talk at Penn in 2012, I took the opportunity to bug you about how to move from Machine Learning to Theory.
    – This list could probably go on for a while.

    Somehow, I am now a quantum computing (really programming languages, but don’t tell the NSF) professor at UChicago. Somehow, I feel like you’ve played a role (though I missed seeing you at the UMD NISQ workshop!).

    Belated Happy 40th, Scott!

  107. Elze Says:

    Your articles and blog posts on quantum computing and complexity theory re-awakened the sense of wonder in me that I had lost during difficult years of my life, and at times they were what I needed to keep going. You are a great science popularizer as well as a great scientist. You explain complex topics with extraordinary clarity, and your humor is incisive, but never mean. Wishing you a happy belated birthday, and many more happy, creativity-filled decades!

  108. Tanuj Khattar Says:

    I’m 25yo, relatively new to the field (started ~1.5 years ago), and mostly self-taught.

    Your book (QCSD), lecture notes, blog and various video lectures on YouTube have been an amazing learning resource for me. I find your written material and talks very exciting and am constantly amazed by your accessible explanations as well as the entertaining puns (one of my favourites: [https://youtu.be/SczraSQE3MY](https://youtu.be/SczraSQE3MY)).

    Kudos to all the great work that you’ve done — you are a constant source of inspiration!

  109. Jan Says:

    Happy birthday! Simply put, I learned a lot from you through this blog. You are educating a large number of people. About the age phase transition (been there 🙂 and using non-pandemic situations as illustration, at some point you sit in a workshop or conference, look around, and realize that you are one of the “older guys”, whereas before, you always belonged to the younger crowd 🙂

  110. Ben Says:

    I discovered your blog not quite a decade ago, and I remember semi-annually to visit again and see what you’ve been up to. Your writing is clear and compelling, and I always feel good after reading it, in ways that I can’t quite describe. Like my fuzzy thoughts about maths and life and our role in the universe have somehow crystallized, thanks to the way you explained your topic.

    So, three months late, happy birthday from a fan. And I hope you’re still feeling continuous 🙂

  111. William Ehlhardt Says:

    A long time ago, I read your piece “Who Can Name the Bigger Number?” It is one of the most delightfully brain-twisting pieces of mathematical writing I’ve ever read. Nearly everyone I’ve ever shared it with has reacted with confusion, both about its subject matter and about my obvious extreme delight/enthusiasm about that subject matter. But that’s not such a big deal – I got what you were talking about, and the pleasure of that understanding remains even if nobody I know shares it.

  112. Keith McLaren Says:

    Ok hands up, this is a pretty majorly late 40th birthday congratulation. But hey I’ve only found your blog in the last two months, so reserve me some slack kid.
    Note the ‘kid’ as I’m now turning 60.
    Hey Scott, you are a superb writer and a very compassionate and sensitive human being by the sounds of it. I’m sure you’re a whacko of a father too. I believe you’re a pretty tip-top scientist as well..
    You mentioned in a blog though (when talking about Scott Alexander’s writing style I think?) that you had reigned in your more carefree younger-self writing style.
    That’s the only error I can see in your ways. Please let it rip as you can old boy.
    That would be a rather good belated birthday present to yourself. And to us.
    Shame not to fully use your gift for writing, which is a significant one.

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